It might be fine for Linus to adopt such a tone, because he knows enough to moderate it up and down according to circumstances. It makes him more expressive. Note that the bug in question really does indicate some serious mistakes in the compiler, with serious consequences, and along with the invective he provides plenty of information. The problem is that hundreds of other kernel developers imitate his most severe tones all the time without such technical detail and even for technical issues where Linus himself wouldn't express disdain that strongly. That lack of "dynamic range" makes them less expressive, so nobody can tell when they're expressing justifiable concern/outrage and when they're just being dicks out of habit.
It's like the second amendment of developer communication. That sort of verbal weaponry should be available, but its use still needs to be justified.
> hundreds of other kernel developers imitate his most severe tones all the time
You are making this up.
If you don't, then you should have no problem producing a handful of examples, because 100s of dev doing this all the time will have LKML and other places overflowing with them.
Fortunately, I don't have to spend part of my vacation wading into that cesspit to satisfy your faux-curiosity. Others have already done so. The canonical example, of course, is Sarah Sharp.
Just look for "crap" or "s--t" or "idiot" or "Viro". Note especially that these are presented as humor, i.e. approvingly and not necessarily showing the worst examples that are just mean without even the saving grace of being slightly funny.
This is not an illusion, not a new or unremarked-upon phenomenon. You're the one making things up when you act as though some reasonable person might believe otherwise.
Since other people have responded to the parent by saying he's making it up... no, he's not. Abusiveness is prevalent in my experience throughout Linux and open source culture. For example, getting flamed for asking reasonable questions at a point where it makes more sense to ask than to keep digging.
Sometimes people deserve it, but often times they just don't. The people doing this are not paragons of judgement like Linus (arguably) is.
It's like the second amendment of developer communication. That sort of verbal weaponry should be available, but its use still needs to be justified.